Question

An umbrella is made by stitching 12 triangular pieces of cloth , each measuring 50cm by 20cm by 50cm .find the area of the cloth used in it

Answer 1

(Area of 1 ∆ular piece of cloth)--- s= 50+20+50/2=60. Now, using Heron's formula--- Area=√s(s-a)×(s-b)(s-c) =√60(60-50)(60-20)(60-50) =√60×10×40×10 = √30×2×5×2×2×20×5×2 =√2×3×5×2×2×5×2×2×2×5×5×2= 200√6 cm². Therefore, area of cloth used= 200√6×12=5878.77cm².

Answer 2

Answer:

5878.77cm²

Step-by-step explanation:

Area of 1 Triangular piece of cloth

s= 50+20+50/2=60.

Now, using Heron's formula.....

Area = √s(s-a)×(s-b)(s-c)

=√60(60-50)(60-20)(60-50)

=√60×10×40×10

= √30×2×5×2×2×20×5×2

=√2×3×5×2×2×5×2×2×2×5×5×2

= 200√6 cm².

Therefore, area of cloth used

= 200√6 × 12                  ( multiplying by 12 as there are 12 pieces )

                                             ( 200√6 is the area of one piece )

= 5878.77cm²